A word from Chase, the 'Iron Man' costume creator:

This is my costume that I made by hand and I am wearing it. It was made with High Density Foam (aka EVA/PVC foam) from Harbor Freight, glued together with hot glue, and then spray painted. LEDs were used to light up the chest and eyes. Total cost of materials was $225 and it took me 6 months to complete. The idea was found from 405th.com and therpf.com.